remove an unused file
remove an unused file

dart-lang/dartdoc,keertip/dartdoc,keertip/dartdoc,dart-lang/dartdoc,dart-lang/dartdoc,astashov/dartdoc,astashov/dartdoc,astashov/dartdoc,keertip/dartdoc,dart-lang/dartdoc,keertip/dartdoc,astashov/dartdoc